It's a familiar truism that at any one moment, financial markets are dominated by either fear or greed. But the healthiest markets are those that are animated by both fear and greed at the same time.

The financial crisis of 2008 was not caused by investment banks betting against the housing market in 2007. It was caused by the fact that too few investors - including all of the big investment banks - bet too heavily on the housing market in the years before 2007.

Technology is supposed to make our lives easier, allowing us to do things more quickly and efficiently. But too often it seems to make things harder, leaving us with fifty-button remote controls, digital cameras with hundreds of mysterious features and book-length manuals, and cars with dashboard systems worthy of the space shuttle.

In the days when corporate downsizing was all the rage, Wall Street took a lot of flak for judging companies too harshly and setting the bar for corporate performance so high that executives felt their only option was to slash payrolls.

Life insurance became popular only when insurance companies stopped emphasizing it as a good investment and sold it instead as a symbolic commitment by fathers to the future well-being of their families.

When all is said and done, cheap gas is an illusion, because our reliance on gas creates a whole series of costs that aren't factored in to the pump price - among them congestion, pollution, and increased risk of accidents.

The stock market has an insidious effect on C.E.O.s' moods, because of its impact not just on their companies but on their own bank accounts.